SDS Volume
Volume 73. Metal and Ammonium Formate Systems, p None
Source Publication
Itkina, L. S.; Nadzharyan, K. A.; Lepeshkov, I. N.; Zh. Neorg. Khim. 26, 1086-91 (1981).
Conditions:
Room Temp: Composition at 25 °C
Compilers:
St. Trendafilova, Chr. Balarew
Methodology:
The isothermal method was used. The mixtures were placed in glass vessels in a thermostat and stirred mechanically. Equilibrium was reached in two weeks. The ammonium content of both phases was determined by the tetraphenylborate method. The barium content was determined gravimetrically as $\ce{BaSO4}$. The composition of the solid phases was determined by Schreinemakers' method, by X-ray diffraction and by thermogravimetry.
Sample Information:
- p.a. grade $\ce{Ba(CHO2)2}$ was recrystallized twice from a 1% solution of formic acid. $\ce{NH4CHO2}$ was prepared by passing ammonia into 90% formic acid. The crystals were washed with ethanol and vacuum dried over sulfuric acid.
Measurement Errors:
Ambient temperature: The temperature was kept constant to within ±0.1°C.
System Components:
- Ammonium formate, $\ce{ NH4CHO2 }$; [540-69-2] NIST WebBook
- Barium formate, $\ce{ Ba(CHO2)2 }$; [541-43-5] NIST WebBook
- Water, $\ce{ H2O }$; [7732-18-5] NIST WebBook
Experimental Data
| 100w1 | 100w2 | m1 (mol/kg) b | m2 (mol/kg) b | Phase (s) () a |
|---|---|---|---|---|
| 60.53 | - | 24.32 | - | A |
| 59.08 | 1.57 | 23.81 | 0.175 | A + B |
| 58.41 | 1.65 | 23.19 | 0.182 | B |
| 56.54 | 1.68 | 21.46 | 0.177 | B |
| 51.23 | 1.62 | 17.23 | 0.151 | B |
| 39.60 | 1.63 | 10.69 | 0.122 | B |
| 38.50 | 2.18 | 10.29 | 0.162 | B |
| 36.72 | 2.22 | 9.537 | 0.160 | B |
| 24.78 | 3.21 | 5.457 | 0.196 | B |
| 11.57 | 9.80 | 2.333 | 0.548 | B |
| - | 23.71 | - | 1.367 | A |
(a) The solid phases are: A = NH4CHO2; B = Ba(CHO2)2.
(b) The molality values were calculated by the compilers.
